Not pulling fuel

Is there fuel leaving the fuel pump? If not, the fuel has likely evaporated over time or drained back into the tank. I've had over a dozen Chrysler products with the same fuel supply system, but only one of them will not draw a prime from the gas tank after it has run out of fuel on the highway. The only way to get that one started is by dribbling a little gas down the carburetor so the engine will run a few seconds each time. The higher engine speed runs the fuel pump faster to help it start drawing fuel from the tank. At the worst, I have to pour gas into the carburetor three times, but usually once or twice will do it.